Overhead carrier-type material handling system



Oct. 20, 1964 R, s. FORESTALL 3,153,391

OVERHEAD CARRIER-TYPE MATERIAL HANDLING sysma 2 Sheets-Sheet 1 Filed Sept. 23, 1959 INVENTOR.

#05097- d' 505572114 Mm, 613 b United States Patent 3,153,391 OVERHEAD CARRIER-TYPE MATERIAL HANDLTNG SYSTEM Robert S. Forestall, Willowick, (this, assignor to The Cleveland Crane & Engineering Company, Wicklifle, (Phio, a corporation of Ohio Filed Sept. 23, 1959, Ser. No. 841,751 1 Claim. (Cl. JAM-"152) The present invention relates to power driven devices and more particularly to the operation thereof in small increments of motion commonly referred to as jogging.

In the operation of many devices, for example, the spotting of a load suspended from the hoist cable forming part of a motorized carrier of an overhead monorail carrier system, the operation of jogging the carrier drive or travel motor may become very important and if not properly performed may result in serious damage to the load, etc.

The principal object of the invention is the provision of a novel and improved electric motor driven device comprising reliable and inexpensive control means which will automatically elfect delicate control over the operation of stopping the device at a predetermined place such as, a crane trolley, overhead monorail carrier, hoist, etc., even though the normal speed of operation of the device may be relatively fast.

The invention resides in certain constructions and combinations and arrangements of parts and further objects and advantages thereof will be apparent to those skilled in the art to which it relates from the following description of preferred embodiments thereof described with reference to the accompanying drawings forming a part of this specification.

FIG. 1 is a side elevational view of a section of an electrified, overhead, monorail carrier system including a power-propelled carrier comprising an electric motor driven hoist and embodying the present invention;

FIG. 2 is a vertical sectional view through the monorail of the system shown in FIG. 1 and the trolley conductor bars mounted on the monorail showing the carrier in end elevation;

FIG. 3 is a wiring diagram of the electric equipment employed in the apparatus shown in FIG. 1; and

FIG. 4 is a view similar to FIG. 3 but showing a modified construction.

While the invention is susceptible of embodiments in many devices it is particularly applicable to motor driven trolleys and is herein shown as embodied in an electric motor propelled carrier of an overhead monorail system equipped with an electric driven hoist.

Referring to the drawings, the overhead, monorail, material handling system shown comprises a monorail having lower, horizontal flange portions 11 upon which a movable carrier C is supported by spaced pairs of flanged wheels 12 for movement along the rail from one location to another by an electric motor 13. The carrier C is provided with a load bar 14 suspended between the two sets of wheels 12 for dependingly supporting an electric motor driven hoist H which includes an electric motor Ztl for rotating the cable drum 21 to which a load grab in the form of a book block G is connected. The power for the motors 13, 26* is supplied from longitudinal conductor bars 24, 25, 26 mounted alongside the monorail 10. In the system illustrated, the motors are of the threephase type and, therefore, three conductor bars are provided. The power for the electric motors is transferred from the conductor bars to the carrier C by three collector shoes 27, 2 3, 29 connected to current collectors 30, 31, 32 mounted on the carrier C and in engagement with the conductor bars 24, 25, 26 respectively. The operation of the motors 13, 20 is controlled from a pendant 3,153,391 Patented Oct. 20, 1964 control station P suspended from the carrier C by a flexible conduit.

The conductor bars or sections are supported alongside the monorail 10 by support brackets 35, 36 preferably made of metal and secured to the web 37 of rail 10. The conductor bars 24, 25, 26 are connected to the brackets 29, 30 by couplings 40, 41 made of molded plastic or other suitable insulating material.

The travel motor 13 is operated by stop push button switch 42, a forward push button switch 45 and a reverse push button switch 46 all on the pendant control station P, and two limit switches 50, 51 mounted on the carrier C and actuated in sequence as the carrier moves along the rail by a cam or trip 52 carried by the rail. Actuation of the switches 50, 51 by the cam or trip 52 stops the carrier at a precise location.

The limit switches 56 and 51 can be connected to the carrier in any convenient manner. In the embodiment shown each is supported upon top of a vertically extend ing bracket 53, the lower end of which is connected to the outer end of a horizontal bracket 54, the inner end of which is connected to the load bar of the carrier C. The trip or cam 52 is connected to the underside of a bracket 55 similar to the brackets 35 previously referred to. The hoist motor 20 is operated by two push button switches 60, 61, an on-olt selector switch 62 on the pendant control station P on the carrier C, and suitable controls, not shown, for automatically lowering and raising the grab G when the carrier is stopped by the cam or trip 52 with the selector switch. 62 in its automatic position. The push button switches 60, 61 when depressed manually cause up and down travel or movement, respectively of the load grab G.

The operator can cause the carrier to move in a forward direction, that is, from left to right as viewed in FIG. 1 by depressing the forward push button switch 45 to close its normally open contacts 65, 66. This establishes a circuit from the line 67 connected to the current collector 30 through the normally closed contacts 70, 71 of stop switch 42, wire 72, now closed contacts 65, 66 of forward switch 45, wire 73, normally closed interlock contacts 74 of motor controller 75, wire 76 and forward solenoid 77 also a part of the motor controller 75, to line 78 connected to the current collector 31.

Energization of motor controller solenoid 77 closes its normally open contacts 80, 81, 82, 83 and opens its normally closed interlock contacts 84. The closing of normally open contacts 80, 81, 82 connects the travel motor 13 to the power lines 67, 78 and 85 in such a manner that the motor operates in the direction to drive the carrier from left to right. Contacts 84 are in series circuit with reverse solenoid 8d of motor controller panel and the opening of these contacts prevents accidental connection of the motor 13 to the power lines such that it would tend to rotate in the reverse direction while operating in the forward direction. The closing of contacts 83 of motor controller establishes a holding circuit for the forward solenoid 77 from the wire 72 through the normally closed contacts as, 91 of trip operated limit switch 50, wire 92, normally closed instant operating contacts 93 of timer relay 94, wire 95, and now closed contacts 83 of motor controller 75 to wire 73. The motor 13 continues to operate in the direction to move the carrier to the right until the operator depresses the stop push button switch 42 to open its closed contacts 70, 71 and break the holding circuit for the forward solenoid 77 of the motor controller, or until the limit switch 50 is actuated by the cam or trip 52 to open its normally closed contacts 9h, 91 and close its normally open contacts 96, 97.

The closing of contacts 96, 97 of limit switch 50 establishes a circuit from the line 67 through the now closed contacts 76, 71 of stop push button switch 42, wire 72,

now closed contacts 9-6, 97 of limit switch Sil, wire ltltl, now closed contacts 191, it'll. of trip operated linit switch 51, wire 103 and operating solenoid 1% of timer relay 94 to line 78. Energization of the operating solenoid 164 of timer relay 94 opens its normally closed instant operating contacts @3, closes its normally open instant operating contacts 165, and after an interval closes its delayed clos- 'mg instant opening, normally open contacts ms. The opening of contacts 90, 91 which are in the holding circuit for the forward solenoid '77 of motor controller 75 breaks the circuit and stops the motor 13 and in turn the carrier.

The closing of contacts 1535 establishes a holding circuit for timer relay 94 around contacts 96, 97 of limit switch 50 which open upon the switch passing beyond the trip 52. The holding circuit for timer relay 94 includes the cam or trip operated limit switch 51 and will be maintained until the limit switch 51 is opened upon its reaching the trip 52.

The closing of contacts 1% establishes a circuit for a motor driven repeating timer or cycle relay lltl having a cam 111 connected to its armatu e shaft which cam has an adjustable lobe that periodically closes a pair of contacts 112, 113 upon actuation of the relay. The period of duration during which the contacts 112, 113 are closed is normally short, preferably a second or less, but the relay is such that this period can be adjusted. The circuit for relay lit established upon the closing of the contacts 1% of timer relay 59 i is from line 67 through the normally closed stop push button switch 52, wire 72, now closed contacts ms of relay 94, Wire 11 5 and relay lit? to line '78. When the normally open contacts 112, 113 of repeat timer relay 11% closes they establish a circuit for the forward solenoid '77 of the motor controller '75 from the wire '72; through the now closed contacts 1% of relay 94, wire 115, contacts 112, 113 of relay Mil, wire '73, normally closed interlock contact M of motor controller '75, wire 76 and forward Operating solenoid '77 of motor controller 75 to line 78. This causes the motor 13 to operate in a direction to advance the carrier or to continue to move the carrier from left to right. The duration of this movement is a function or" the length of time that the contacts 112, M3 remain closed, which in turn is dependent upon the length of the high lobe of cam ill which lobe, as previously stated, is adjustable.

The interval between the deenergization of the forward solenoid '77 of the motor controller 75 upon the opening of the limit switch 5%} and the time the forward solenoid '77 is first energized through the repeat timer relay llil depends upon the adjustment of the timer relay 94, the contacts we of which are of the delayed-closing-instantopening type. The motor 13 will be periodically energized for short periods of time upon each closing of the normally open contacts 112, 113 of switc by the cam 111 until the carrier has been jogged in the forward direction sufficiently far for the trip 52 to open the limit switch 51.

The opening of the limit switch 51 breaks the holding circuit for the operating soenoid 1% of timer relay 94 allowing its normally closed contacts 95 to reclose to recondition the holding circuit about the push button switch 45 for future operation, and its normally open contacts 195, ms to reopen. The opening of the contacts 165 of relay 94 prevents reestablishment of the holding circuit around the normally open contacts as, 97 of limit switch 5t) as and when the limit switch 51 is moved away from the trip 52 and its contacts allowed to reclose. The opening of the normally open contacts me of relay 94 deenergizes the repeat timer lid with the result that the carrier C comes to a stop at a desired location.

From the foregoing description of the operation of the embodiment of the invention shown in FIGS. 1 and 2 it will be apparent that as the carrier C approaches a desired station or location the limit switch 5% will be actuated by the trip 52. to stop the motor 13 which drives the carrier. it is assumed that the carrier is moving at relatively high speed at this time and that it will coast forwardly a short distance under its momentum. Alternatively a solenoid operating brake could be employed to stop the carrier almost instantaneously with the disconnecting of the drive motor 13 from the power lines. In either event operation of the timer relay 94 will, after a predetermined period, energize the motor driven repeat timer relay lit) whereupon the motor 13 and in turn the carrier C will be jogged forward short intervals depending upon the adjustment of the timer relay Illtl towards its ultimate de sired stop position. When this position is reached the limit switch 51 will be opened by the trip 52 and the carrier will be stopped in the desired location.

The motor 13 can be operated in the reverse direction by the operator depressing the reverse push button switch 46 to close its normally open contacts 12th, 121. The closing of the normally open contacts 126, 121 of reverse push button switch 46 establishes a circuit from the line 6'7 through the now closed contacts '76, '71 of stop switch 42, wire '72, now closed contacts 12%, 321 of reverse switch as, wire i122 normally closed interlock contacts 84 of motor controller '75, wire 123, and reverse solenoid 86 of motor controller to line 7%. The energization of the reverse solenoid as of motor controller '75 closes its normally open contacts 125, 126, 127 connecting the motor l3 to the power lines 67, '78, in such a manner that the motor l3 rotates in a direction to reverse the direction of travel of the carrier C and opens its normally closed interlock contacts '74 which are in series circuit with the forward solenoid '77 of the motor controller '75 preventing accidental connection of the motor 13 with the power line in such a manner that it tends to rotate in a forwardly direction while operating in the reverse direction.

FIG. 4 shows an alternative ernbodirnenL in which the motor driven repeat timer or sequence relay shown in the preferred embodiment is replaced by two solenoid operated timer relays. All of the circuitry shown in PEG. 4 will not be described in detail since most of it is the same as previously described. The duplicate parts are designated by the same reference characters. The operation of the embodinent shown in PEG. 4 is the same as that of the preferred embodiment until the first limit switch is actuated by the trip 52 to energize timing relay $4 and establish its holding circuit. The only difference up to this point is the fact that the limit switch 51 is now located between the wire 72 and the limit switch 5th.

With the embodiment shown in H53. 4 tie closing of the delayed-closing-instant open contacts 1% of timer relay 9% after the desired interval establishes a circuit from line 67 through the normally closed contacts 76 '71 of stop switch 42, wire '?2, now normally closed contacts idll, 1 52 of limit switch 53, wire 1%, now closed contacts 1% of timer relay 94, wire 13%, normally closed contacts 131 of timer relay 132, wire '73, normally closed interlock contacts '74- of motor controller 75, wire as and forward solenoid 77 of motor controller '75 to line 73. The energization of forward solenoid 7! of motor controller '75 connects the motor 13 to the power lines in such a manner that it rotates in the forward direction, that is in the direction to advance the carrier or move it from left to right as viewed in PEG. 1. in this embodiment the timer relay $4 is provided with a second pair of delayed-e10sing-instant-open contacts 135 and the closing of these contacts establishes a circuit from the wire 72 through the now closed contacts 135 of timer relay 94, wire instant-closed-delayed-opening normaliy closed contacts of time relay 142, wire 1 3 and operating solenoid 14-4 of relay to line Energiz tion of the operating solenoids 14d of relay 132 ctuates the relay to open its delayed-o zenin -instan -closing contacts 131 and close its instant-opening-delayed-closing contacts after the elapse or a predetermined time.

The opening of contacts 131 of relay 132 breaks the holding circuit for the forward solenoid 77 of the motor controller 75 thus stopping the motor. The closing of contacts 145 of relay 132 establishes a circuit from the Wire 72 through the now closed contacts 145, Wire 150 and operating solenoid 151 of relay 142 to line 78. Energization of the operating solenoid 151 of relay 142 actuates the relay to open its instant-closing-timed opening contacts 141 after the elapse of a predetermined interval. The opening contacts 141 of relay 142 breaks the circuit for timer relays 132 deenergizing the operating solenoid 144 allowing its normally closed contacts 131 to reclose and its normally open contacts 145 to reopen. The reclosing of the normally open contacts 131 reestablishes the circuit for the forward solenoid 77 of motor controller 75 reconnecting the motor 13 to the power lines. The opening of the contacts 145 of relay 132 breaks the circuit for the operating solenoid 151 of the timer relay 1142 allowing the contacts 141 thereof to reclose and reestablish the operating circuit for the relay 132.

From the foregoing it will be apparent that the timer relays 132, 142 are alternately operated to connect and disconnect the motor 13 with and from the power lines causing the motor to be intermittently operated and the carrier C jogged in a forwardly direction. This operation of the carrier continues until the limit switch 51 is opened by the trip or cam 52 breaking the holding circuit for timer relay 94 and in turn opening the contacts 106 thereof thus preventing reestablishmcnt of the circuit to the forward solenoid 77 of the motor controller 75 upon the next reclosing of the normally closed contacts 131 of relay 132. The carrier is now in its desired station or position.

From the foregoing description of the preferred embodiments of this invention, it is believed that it will be apparent that the objects thereof heretofore enumerated and others have been accomplished and that there has been provided a motor driven apparatus having simple, reliable controls which will effectively stop the device at a predetermined place even though its normal speed of the operation may be relatively fast.

Having thus described my invention, what 1 claim is:

in a high-speed overhead monorail carrier type material handling system, an overhead rail, a carrier supported on said rail for movement therealong, an electric motor for moving said carrier along said rail, circuit means for actuating said motor when completed and for deactuating said motor when broken, first switch means supported by said carrier and having a first position completing said circuit means and a second position breaking said circuit means, means positioned at a predetermined point along said rail for actuating said first switch means from its first position to its second position breaking said circuit means, timing means actuated by operation of said first switch means to its said second position for periodically completing and breaking said circuit means for actuating and deactuating said motor sequentially to move said carrier intermittently along said rail, second switch means supported by said carrier for stopping the operation of said timing means and effecting deactuation of said motor, and means located along said rail for actuating said second switch means when said carrier reaches a predetermined position along said rail.

References (Cited in the file of this patent UNITED STATES PATENTS 1,940,887 Schaelchlin Dec. 26, 1933 1,988,855 Neuman Ian. 22, 1935 2,397,185 Krapf Mar. 26, 1946 2,530,749 Yardeny et a1. Nov. 21, 1950 2,537,269 Harding Jan. 9, 1951 2,675,511 Kotzler Apr. 13, 1954 2,735,975 Gallimore Feb. 2 1, 1956 2,773,231 Adriansen et al. Dec. 4, 1956 

